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OBJECTIVES: Oral hairy leukoplakia (HL) is an acan-thotic, hyperparakeratotic lesion characterised by the presence of a replicative Epstein-Barr virus (EBV) infection in the superficial and adjoining layers of the epithelium. EBV or its gene products are capable of modifying epithelial differentiation. The aim of this study was to establish whether the presence of EBV was associated with an alteration in cell turnover by assessing bromodeoxyuridine (BrdU) incorporation and Ki 67 expression in lesional tissue and control mucosa.
METHODS: Biopsies of HL together with age, site and sex matched controls ( n = 7 and 8 respectively) were incubated in 200 μM BrdU in vitro , fixed in methacarn and processed to paraffin wax. Following acid hydrolysis, incorporated BrdU and Ki 67 were identified in serial 5 fim sections using a three-stage immunoperoxidase technique and cell density expressed as the number of positive cells per mm basement membrane length.
RESULTS: Overall, there was no difference in the number of BrdU positive cells per mm basement membrane length between control and HL tissue. However, within HL alone, the presence'of focal EBV replication was associated with a significant reduction in the number of basal cells incorporating BrdU compared to adjacent EBV free areas (P < 0.05). There was no significant difference between Ki 67 positive cells in control and HL tissue and no evidence of a reduction of Ki 67 positive cells in areas associated with EBV replication.
CONCLUSIONS: These results suggest that there is no evidence of a generalised alteration of the proliferative capacity of basal cells in HL, although the focal reduction in BrdU incorporation may reflect subtle changes on cell turnover by EBV infection. 相似文献
METHODS: Biopsies of HL together with age, site and sex matched controls ( n = 7 and 8 respectively) were incubated in 200 μM BrdU in vitro , fixed in methacarn and processed to paraffin wax. Following acid hydrolysis, incorporated BrdU and Ki 67 were identified in serial 5 fim sections using a three-stage immunoperoxidase technique and cell density expressed as the number of positive cells per mm basement membrane length.
RESULTS: Overall, there was no difference in the number of BrdU positive cells per mm basement membrane length between control and HL tissue. However, within HL alone, the presence'of focal EBV replication was associated with a significant reduction in the number of basal cells incorporating BrdU compared to adjacent EBV free areas (P < 0.05). There was no significant difference between Ki 67 positive cells in control and HL tissue and no evidence of a reduction of Ki 67 positive cells in areas associated with EBV replication.
CONCLUSIONS: These results suggest that there is no evidence of a generalised alteration of the proliferative capacity of basal cells in HL, although the focal reduction in BrdU incorporation may reflect subtle changes on cell turnover by EBV infection. 相似文献
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Tomasz Rogula Marijan Koprivanac Michał Robert Janik Jacob A. Petrosky Amy S. Nowacki Agnieszka Dombrowska Matthew Kroh Stacy Brethauer Ali Aminian Philip Schauer 《Obesity surgery》2018,28(9):2589-2596
Objective
The aim was to compare clinical outcomes of patients treated with totally robotic Roux-en-Y gastric bypass (TRRYGB) with those treated with the different laparoscopic Roux-en-Y gastric bypass (LRYGB) techniques.Summary Background Data
The clinical benefit of the robotic approach to bariatric surgery compared to the standard laparoscopic approach is unclear. There are no studies directly comparing outcomes of TRRYGB with different LRYGB techniques.Methods
Outcomes of 578 obese patients who underwent RYGB between 2011 and 2014 at an academic center were assessed. Multivariable analysis and propensity matching were used for comparing TRRYGB to different LRYGB techniques, including 21-mm EEA circular-stapled gastrojejunal anastomosis (GJA, LRYGB-21CS), linear-stapled GJA (LRYGB-LS), and hand-sewn GJA (LRYGB-HS).Results
The TRRYGB technique required a longer mean operative time compared to the other groups, respectively 204?±?46 vs. 139?±?30 min (LRYGB-21CS), 206?±?37 vs. 158?±?30 min (LRYGB-LS), and 210?±?36 vs. 167?±?30 min (LRYGB-HS). TRRYGB experienced a lower stricture rate (2 vs. 17%, P?=?0.003), shorter hospital stay (2.6?±?1.2 vs. 4.3?±?5.5 days, P?=?0.008), and lower readmission rate (12 vs. 28%, P?=?0.009). No significant differences in outcomes were observed when comparing RRYGB to LRYGB-LS or LRYGB-HS.Conclusions
TRRYGB increases operative time compared to all LRYGB techniques. TRRYGB was superior to LRYGB-21CS in terms of significantly shorter hospital stay, lower readmission rate, and less frequent GJA stricture formation. TRRYGB provides no clinical advantages over the LRYGB-LS and LRYGB-HS techniques.55.
Strangulation in child abuse: CT diagnosis 总被引:2,自引:0,他引:2
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients. 相似文献
56.
Artur Dziadkiewicz Monika Białecka Piotr Janik Jarosław Sławek 《Neurologia i neurochirurgia polska》2013,47(4):387-392
Hemiparkinsonism-hemiatrophy (HPHA) is a rare neurological syndrome. The main clinical features of HPHA consist of atrophy of one side of the body (face, trunk, limbs), ipsilateral hemiparkinsonism (bradykinesia, rigidity, tremor) and in many cases dystonia. There are no data on prevalence of HPHA as the condition is rare. The mean age of parkinsonism onset is earlier than in idiopathic Parkinson disease (43.7 years, range: 15–63). Changes in magnetic resonance imaging (MRI) (cortical, basal ganglia atrophy contralaterally to the side of clinical presentation) are described in 30% of patients. The pathogenesis of HPHA is unknown, but in many cases a history of prenatal injuries was reported.We present two male patients with HPHA – 45 and 55 years old, with left-sided parkinsonism, dystonia and hemiatrophy (to our knowledge, the first Polish cases). Both patients had no atrophic changes in MRI and levodopa treatment was ineffective. In the discussion the authors review current literature on HPHA. 相似文献
57.
Purpose
The purpose of this study was to determine, in a pediatric population less than 5 years of age, which size catheter is ideal for central venous access via the subclavian and internal jugular vein based on the children’s age, weight, and height.Methods
This was a retrospective chart review of children less than 5 years of age at The Children’s Hospital in Denver, Colorado who underwent subclavian or internal jugular central venous catheter placement from January 1, 1998 through December 31, 2001. Age, height, weight, primary disease, access site, type of central venous catheter, size of central venous catheter, and complications were recorded. Age, weight, and height were stratified and compared with catheter size to determine any correlation between age, weight, height, and complications.Results
There were 430 central venous catheters placed via the subclavian or internal jugular vein in 331 patients less than 5 years old. One hundred ninety-five catheters (45.4%) were less than 6F in size, and 235 (54.6%) catheters were ≥6F in size. Children, who were between 0.5 and 0.99 years old, 5 to 7.49 kg in weight, 7.5 to 9.99 kg in weight, and 60 to 74.9 cm in height had higher complication rates (P < .05) when catheters ≥6F were inserted. Children who were greater than 1 year of age, greater than 10 kg in weight, and longer than 75 cm in height did not experience a significant difference (P > .05) in complications versus catheter size.Conclusions
The choice of central venous catheter size should be predicated, not only on the primary disease, but also on the child’s age, weight, and height. Insertion of central venous catheters larger than 6F in children less than 1 year of age, less than 10 kg in weight, or less than 75 cm in height, was associated with higher complications compared with other settings. 相似文献58.
JS Tsang Chi Chung Foo Jeremy Yip Hok Kwok Choi Wai Lun Law Oswens Siu Hung Lo 《The surgeon》2021,19(3):150-155
IntroductionThe difference in outcome between right (RCD) and left colonic diverticulitis (LCD) is not well established. The aim of this study was to analyse the presentation and surgical outcome of RCD versus left-sided disease following emergency surgery.MethodWe conducted a retrospective review of patients presenting with acute diverticulitis over a 10-year period from 2004 to 2014 to a tertiary unit. Patient demographics, Hinchey classification, need for emergency surgery, perioperative outcome and recurrence were evaluated.ResultsIn total 360 patients presented with acute diverticulitis, 218 (61%) were right-sided and 142 (39%) were left-sided. The mean age (57 yrs vs 68 yrs) and median length of stay (4 days vs 5 days) were significantly less in RCD (p < 0.001). The need for emergency surgery was similar between RCD and LCD (30.7% vs 23.2%, p = 0.12). Sixty-seven (31%) patients with RCD required emergency surgery, 42 (62.7%) of these were based on a presumptive diagnosis of appendicitis and underwent laparoscopic appendicectomy only. Operative morbidity (10.4% vs 51.5%, p < 0.001) and mortality were significantly higher in LCD (1.5% v 15.2%, p = 0.007). Subgroup analysis of non-appendicectomy, RCD patients, showed LCD were more likely to require surgery (11.5% vs 23.2%, p = 0.003). There was no difference in recurrence (p = 0.6).ConclusionRight colonic diverticulitis patients are younger and disease course is more benign compared to LCD. Presentation can be confused with appendicitis without proper imaging. In the rare cases where emergency surgery is required, RCD is associated with a lower operative morbidity and mortality compared to left-sided disease. 相似文献
59.
JS Pooni Dr DWL Hukins PF Harris RC Hilton KE Davies 《Surgical and radiologic anatomy : SRA》1986,8(3):175-182
Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc. 相似文献
60.